UCC28810,UCC28811,pdf(LED Ligh
The UCC28810 and UCC28811 are general lighTIng power controllers for low to medium power lumens applicaTIons requiring power factor correcTIon and EMC compliance. It is designed for controlling a flyback, buck or boost converter operaTIng in critical conduction mode. It features a transconductance voltage amplifier for feedback error processing, a simple current reference generator for generating a current command proportional to the input voltage, a current-sense (PWM) comparator, PWM logic and a totem-pole driver for driving an external FET.
In the critical conduction mode operation, the PWM circuit is self-oscillating with the turn-on being governed by a transformer zero energy detector (TZE pin) and the turn-off being governed by the current sense comparator.